[PATCH] usbtest, Kconfig and misc

Minor patches:

- resend of the Config.in patch, updated to Kconfig,
   plus makes 'usbtest' modular when usb is;

- hmm, "usbfs" isn't locking here.  protect.  fix
   is basically from martin:  add/use a semaphore.

- that one-liner to make sure get_configuration is
   called correctly (with funkier test firmware).

- new 'realworld' module param can be used to turn
   off the real-world accomodations and be stricter
   about what device failures make ch9 tests fail.

drivers/usb/misc/Kconfig

@@ -99,10 +99,13 @@ config USB_SPEEDTOUCH
 
 config USB_TEST
 	tristate "USB testing driver (DEVELOPMENT)"
-	depends on USB_DEVICEFS && EXPERIMENTAL
+	depends on USB && USB_DEVICEFS && EXPERIMENTAL
 	help
 
 	  This driver is for testing host controller software.  It is used
 	  with specialized device firmware for regression and stress testing,
 	  to help prevent problems from cropping up with "real" drivers.
 
+	  See <http://www.linux-usb.org/usbtest> for more information,
+	  including sample test device firmware and "how to use it".
+

drivers/usb/misc/usbtest.c

@@ -51,14 +51,10 @@ struct usbtest_info {
 };
 
 /* this is accessed only through usbfs ioctl calls.
- * one ioctl to issue a test ... no locking needed!!!
+ * one ioctl to issue a test ... one lock per device.
  * tests create other threads if they need them.
  * urbs and buffers are allocated dynamically,
  * and data generated deterministically.
- *
- * there's a minor complication on rmmod, since
- * usbfs.disconnect() waits till our ioctl completes.
- * unplug works fine since we'll see real i/o errors.
  */
 struct usbtest_dev {
 	struct usb_interface	*intf;
@@ -66,6 +62,7 @@ struct usbtest_dev {
 	char			id [32];
 	int			in_pipe;
 	int			out_pipe;
+	struct semaphore	sem;
 
 #define TBUF_SIZE	256
 	u8			*buf;
@@ -282,6 +279,10 @@ static int perform_sglist (
  * or remote wakeup (which needs human interaction).
  */
 
+static int realworld = 1;
+MODULE_PARM (realworld, "i");
+MODULE_PARM_DESC (realworld, "clear to demand stricter ch9 compliance");
+
 static int get_altsetting (struct usbtest_dev *dev)
 {
 	struct usb_interface	*iface = dev->intf;
@@ -366,13 +367,11 @@ static int is_good_config (char *buf, int len)
 	case USB_DT_OTHER_SPEED_CONFIG:
 		if (config->bLength != 9)
 			return 0;
-#if 0
 		/* this bit 'must be 1' but often isn't */
-		if (!(config->bmAttributes & 0x80)) {
+		if (!realworld && !(config->bmAttributes & 0x80)) {
 			dbg ("high bit of config attributes not set");
 			return 0;
 		}
-#endif
 		if (config->bmAttributes & 0x1f)	/* reserved == 0 */
 			return 0;
 		break;
@@ -424,7 +423,7 @@ static int ch9_postconfig (struct usbtest_dev *dev)
 		}
 
 		/* [real world] get/set unimplemented if there's only one */
-		if (iface->num_altsetting == 1)
+		if (realworld && iface->num_altsetting == 1)
 			continue;
 
 		/* [9.4.10] set_interface */
@@ -446,7 +445,7 @@ static int ch9_postconfig (struct usbtest_dev *dev)
 	}
 
 	/* [real world] get_config unimplemented if there's only one */
-	if (udev->descriptor.bNumConfigurations != 1) {
+	if (!realworld || udev->descriptor.bNumConfigurations != 1) {
 		int	expected = udev->actconfig->desc.bConfigurationValue;
 
 		/* [9.4.2] get_configuration always works
@@ -454,7 +453,8 @@ static int ch9_postconfig (struct usbtest_dev *dev)
 		 * won't return config descriptors except before set_config.
 		 */
 		retval = usb_control_msg (udev, usb_rcvctrlpipe (udev, 0),
-				USB_REQ_GET_CONFIGURATION, USB_RECIP_DEVICE,
+				USB_REQ_GET_CONFIGURATION,
+				USB_DIR_IN | USB_RECIP_DEVICE,
 				0, 0, dev->buf, 1, HZ * USB_CTRL_GET_TIMEOUT);
 		if (retval != 1 || dev->buf [0] != expected) {
 			dbg ("%s get config --> %d (%d)", dev->id, retval,
@@ -563,7 +563,8 @@ static int ch9_postconfig (struct usbtest_dev *dev)
  * threads and request completion.
  */
 
-static int usbtest_ioctl (struct usb_interface *intf, unsigned int code, void *buf)
+static int
+usbtest_ioctl (struct usb_interface *intf, unsigned int code, void *buf)
 {
 	struct usbtest_dev	*dev = dev_get_drvdata (&intf->dev);
 	struct usb_device	*udev = testdev_to_usbdev (dev);
@@ -584,6 +585,9 @@ static int usbtest_ioctl (struct usb_interface *intf, unsigned int code, void *b
 			|| param->sglen < 0 || param->vary < 0)
 		return -EINVAL;
 
+	if (down_interruptible (&dev->sem))
+		return -ERESTARTSYS;
+
 	/* some devices, like ez-usb default devices, need a non-default
 	 * altsetting to have any active endpoints.  some tests change
 	 * altsettings; force a default so most tests don't need to check.
@@ -591,12 +595,15 @@ static int usbtest_ioctl (struct usb_interface *intf, unsigned int code, void *b
 	if (dev->info->alt >= 0) {
 	    	int	res;
 
-		if (intf->altsetting->desc.bInterfaceNumber)
+		if (intf->altsetting->desc.bInterfaceNumber) {
+			up (&dev->sem);
 			return -ENODEV;
+		}
 		res = set_altsetting (dev, dev->info->alt);
 		if (res) {
 			err ("%s: set altsetting to %d failed, %d",
 					dev->id, dev->info->alt, res);
+			up (&dev->sem);
 			return res;
 		}
 	}
@@ -770,6 +777,7 @@ static int usbtest_ioctl (struct usb_interface *intf, unsigned int code, void *b
 		param->duration.tv_usec += 1000 * 1000;
 		param->duration.tv_sec -= 1;
 	}
+	up (&dev->sem);
 	return retval;
 }
 
@@ -819,6 +827,7 @@ usbtest_probe (struct usb_interface *intf, const struct usb_device_id *id)
 	memset (dev, 0, sizeof *dev);
 	info = (struct usbtest_info *) id->driver_info;
 	dev->info = info;
+	init_MUTEX (&dev->sem);
 
 	/* use the same kind of id the hid driver shows */
 	snprintf (dev->id, sizeof dev->id, "%s-%s:%d",
@@ -874,6 +883,8 @@ static void usbtest_disconnect (struct usb_interface *intf)
 {
 	struct usbtest_dev	*dev = dev_get_drvdata (&intf->dev);
 
+	down (&dev->sem);
+
 	dev_set_drvdata (&intf->dev, 0);
 	info ("unbound %s", dev->id);
 	kfree (intf->private_data);